Facile Synthesis of Bumpy-Structured ZnO-ZnS Core-Shell Microspheres with Enhanced Photocatalytic Performance

Abstract

Zinc oxide is considered an outstanding photocatalyst candidate, but its low photo-corrosion resistance is a problem to be solved. In the ZnO-ZnS core-shell structure, ZnS acts as a protective layer for the ZnO core, and thus, it can enhance stability and long-term performance. The ZnO-ZnS core-shell structure is synthesized into various nanoscale morphologies with high specific surface areas to improve photocatalytic efficiency. However, they are easily agglomerated and are hard to separate from reaction media. In this study, micro-sized bumpy spheres of ZnO-ZnS core-shell structure were prepared via facile chemical transformation of as-prepared ZnO. After sulfurization of the ZnO template, it was confirmed through SEM, TEM, EDS, and XPS analysis that a uniform ZnS shell layer was formed without significant change in the initial ZnO morphology. The ZnO-ZnS core-shell microsphere has shown superior efficiency and stability in the photocatalytic degradation of Rhodamine B compared with pristine ZnO microspheres